Case: Norman Doors

The book's signature example — confusing doors are now literally called "Norman doors."

The story: A friend got trapped between two rows of identical glass swinging doors in a European post office. The designer aimed for beauty: no visible hardware, pillars, or hinges. Distracted, the friend drifted toward the (invisible) hinge side and pushed there → nothing happened → mild panic, until others walked through easily.

The lesson: A swinging door must be pushed on its unsupported edge; with no visible cue you can't know which side. This is a failure of discoverability. The fix needs no loss of aesthetics: a vertical plate on the push side, or visible supporting pillars — natural Signifiers, naturally interpreted, no labels.

Generalized claim: When a device as simple as a door needs a sign ("push"/"pull"/"slide") to be operated, it is poorly designed. Whenever you see a hand-lettered sign taped on a door/switch/product explaining how to work it, you are looking at bad design.

Related door examples: sliding doors "seldom done well" (Amtrak toilet handle signifies pull but must rotate+slide); cabinet push-to-open doors that contradict their glass-visible interior; Paris Métro doors you must open yourself (cultural-norm trap).

Demonstrates Affordances vs Signifiers and discoverability.

Confidence

1.0 — flagship example.

Sources: ["DOET ch.1 opening p.1-3; ch.4 'The Problem with Doors' p.132-135"]